One man who knows the path ahead for the victims is Mike Welsch, and amputee runner who was in the 18th mile of his 10th Boston Marathon last month when police said there had been an explosion.

"They said, 'There's arms and legs all over the place. You can't go into Boston. There's been two big explosions,'" Welsch said.

At Next Step Orthotics and Prosthetics in Manchester, workers heard the news with the increasing knowledge that they would likely be called on to help some of the victims.

"There was a sense of guilt a little bit for us because the last thing we want to see is people get hurt," said Matthew Albuquerque of Next Step.

Albuquerque said the team at Next Step will be among those helping victims who lost limbs in the coming months.

"If we can be on the side of creating hope for people, based on example and the things that we do, that's the best thing we can do for the people that are injured right now," he said.

Jason Lalla lost his leg 22 years ago in a motorcycle accident and is now a professional prosthetist. He said the first couple of years for victims are a roller coaster.

"You're going to have days that are really great," he said. "You've mastered some goal that you had set and things are going well, and then you'll have days where you kind of crash for whatever reason. Emotionally, physically, you're wiped out. And then over time you get some consistency."

The professionals at Next Step said they are wary of the goodhearted offers coming in from across the country offering free limbs to victims of the Boston bombing. They said the fit and fine-tuning for a prosthetic require an ongoing relationship.

"Great technology is nothing without good prosthetic care," Welsch said. "And a good-fitting socket and great care is lessened by not having great technology."

Lalla knows the value of a well-made and well-fitted prosthetic. He's a Paralympic downhill ski champion and a downhill mountain biker.

"When I say I understand, they go, 'OK. So maybe you do understand,' Lalla said. "So there is a more immediate connection."

Physically, amputees describe phantom pains and sensing that their limb is still there. Lalla said he recalls his as being excruciating.

"It felt like an extension cord that was cut, and the current was trying to jump from this end to this end, and the other end wasn't there," he said.

The intense emotional devastation of losing a limb can traumatize the entire family. Lalla said he remembers it well, thinking he would never ride again, never date and that his life was over.

"If there's any message I can tell the family members and the friends, it's that heart isn't in a limb. Drive isn't in a limb," Lalla said. "All of those things that made a person who they are is not in a leg. If those people were competitors before, they will compete again."

Welsch is comfortable showing his limb and the process of getting into the socket. It starts by rolling on a gel sock for comfort. When News 9 visited, he was wearing a bionic ankle that can be adjusted with a smartphone. It's called a BiOM and is worth $50,000.

The prosthetic of choice for most amputee runners is a blade device with no heel. But Welsch runs on a more old-fashioned prosthetic.

"I don't want a running leg," he said. "I'm old and I'm stubborn and I'm slow."

The choice of a prosthetic is a personal one. A woman who wants to wear a dress and high heels could choose a realistic option, but Albuquerque said few people are going that direction these days, opting instead for customized sockets.

"There's a quasi-Terminator, high-tech look that a lot of people like," he said.

The advice for new amputees fighting to rebuild their bodies and their lives is to stay active.

"You can do this," Welsch said. "You can run if you decide to. You can do whatever you want."

"Loss of limb, it can and it will make you stronger," Lalla said. "You have to overcome those things, and that's an accomplishment in and of itself."

LAWS TAKE EFFECT. IT HAS NOT BEEN THREE WEEKS SINCE THE MARATHON BOMBING, BUT MANY WITH THE MOST DEVASTATED INJURIES ARE IN RECOVERY AND THE HAVE. FIST -- 15 PEOPLE LOST LIMBS AND SOME HAVE BEEN IN CONTACT WITH A NEW HAMPSHIRE COMPANY THAT PROVIDES CUTTING EDGE PROSTHETICS. TONIGHT, WE MEET SOME OF THE PROFESSIONALS AND LONGTIME CLIENTS TO SEE WHAT THE COMPANY OFFERS AND HOW THEY CAN PROVIDE HOPE AND HEALING TO THE VICTIMS. ? A PERFECT, SPRING DAY IN BOSTON. THOUSANDS OF PEOPLE ARE IN THE CITY FOR THE 117TH RUNNING OF THE BOSTON MARATHON. THIS WAS HIS 10TH BOSTON MARATHON. IT WAS CUT SHORT AT MILE 18. THERE HAD BEEN AN EXPLOSION. ? ARMS AND LEGS ALL OVER THE PLACE. TWO BIG EXPLOSIONS. UNTHINKABLE AMOUNTS OF BLOOD STAINING THE PAVEMENT AT THE FINISH LINE. THE TERRIFIED FACES OF THOSE RUNNING AWAY. THE FRANTIC ATTEMPTS TO STOP THE BLEEDING. THERE WAS A LITTLE SENSE OF GUILT FOR US BECAUSE THE LAST THING THAT WE WANT TO SEE IF PEOPLE GET HURT. WE MET MATTHEW AND THE TEAM AT THEIR MANCHESTER OFFICE TWO WEEKS AFTER THE BOMBING TO LEARN ABOUT THE OPTIONS THAT VICTIMS WILL HAVE IN THE COMING MONTHS. IF WE COULD BE ON THE SIDE OF CREATING HOPE FOR PEOPLE BASED ON THE EXAMPLES AND THINGS THAT WE DO, I THINK THAT IS THE BEST THING WE COULD DO FOR THE PEOPLE THAT ARE INJURED RIGHT NOW. HE LOST HIS LIKE 22 YEARS AGO IN A MOTORCYCLE ACCIDENT AND IS NOW A PROFESSIONAL. HE SAYS THE FIRST COUPLE OF YEARS ARE A ROLLER COASTER. YOU WILL HAVE DAYS WHERE EVERYTHING IS GREAT AND YOU HAVE MASTERED SOME GOALS YOU HAD SET AND THINGS HAVE GONE WELL. THEN YOU HAVE DAYS WHEN YOU CRASH. FOR WHATEVER REASON, YOU ARE A EMOTIONALLY, PHYSICALLY WIPED OUT. THAT TIME DOES THIS AND THEN THIS AND THEN THIS. OVER TIME, YOU GET CONSISTENCY TO REQUEST THE PROFESSIONALS HERE ARE WARY OF THE GOOD HEARTED OFFERS COMING FROM AROUND THE CLOCK -- THE COUNTRY OFFERING FREE LIMBS. THIS REQUIRES AN ONGOING RELATIONSHIP. GREAT TECHNOLOGY IS NOTHING WITHOUT GOOD PROSTHETIC CARE. JASON WALKS THE WALK AND TALK THE TALK. HE IS A DOWNHILL CHAMPION AND A DOWNHILL MOUNTAIN BIKER. I SAY, LOOK, I HAVE BEEN THROUGH THIS. THEY SAY, MAYBE YOU UNDERSTAND. THERE IS A MORE IMMEDIATE CONNECTION. PHYSICALLY, AMPUTEES DESCRIBED PAIN AS IF THE LIMB IS STILL THERE. JASON RECALLS HIS AS BEING EXCRUCIATING PROGRESS IT FELT LIKE AN EXTENSION CORD THAT WAS CUT AND THE CURRENT WAS TRYING TO JUMP FROM THIS AND TO THE OTHER END AND THE OTHER END WAS NOT THERE. LOSING A LIMB TRAUMATIZES THE ENTIRE FAMILY. JASON REMEMBERS IT WELL, THINKING HE WOULD NEVER RIDE AGAIN OR NEVER DATE, THAT HIS LIFE WAS OVER. WHAT I CAN TELL FAMILY MEMBERS AND FRIENDS IS THAT PART IS NOT IN A LIMB. DRIVE IS NOT IN A LIMB. ALL OF THOSE THINGS THAT MADE THAT PERSON WHO THEY ARE, IT IS NOT IN A LAKE. THOUGH PEOPLE -- THE PEOPLE WERE COMPETITORS BEFORE AND THEY WILL COMPETE AGAIN. HE IS COMFORTABLE SHOWING HIS LIMB AND THE PROCESS OF GETTING IT IN THE SOCK IT. IT STARTS BY ROLLING ON A JAL STOCK FOR COMFORT. TODAY, HE IS ADJUSTING IT TO BUY A SMARTPHONE. IT IS WORTH $50,000. IT COMPRESSES THE SPRING AND LETS IT GO AT A CERTAIN TIME. THIS IS THE PROSTATIC OF CHOICE FOR MOST RUNNERS, A DEVICE WITH NO DEAL. THIS PROFESSIONAL AND MARATHON SWIMMER AND RUNNER ARE IN FULL AGREEMENT ON THEIR ADVICE TO THE NEW NTT, FIGHTING TO REBUILD THEIR BODY AND THE LIVES. STAY ACTIVE. YOU CAN DO THIS. YOU CAN RUN IF YOU DECIDE TO. YOU CAN DO WHATEVER YOU WANT . IT WILL MAKE YOU STRONGER. YOU HAVE TO OVERCOME THOSE